Electronic cigarette makers are getting bold with their advertising, using provocative new print ads and celebrity endorsements on TV. But public health advocates say these images are luring kids to hook them on nicotine.

The latest ad for blu eCigs, for example, which ran in the Sports Illustrated swimsuit edition, features an itsy bitsy bikini bottom emblazoned with the company name and includes the tagline “Slim. Charged. Ready to go.” You don’t see the model’s face. The frame is from pierced belly button to mid thigh. It left Stan Glantz, a professor of medicine at the University of California, San Francisco, struggling for a delicate way to describe it.

“The advertising just hit a new high in terms of chutzpah,” says Glantz, director of the Center for Tobacco Control Research and Education. Using sex to sell cigarettes is nothing new, he says, and e cigarettes are pushing the envelope because they’re unregulated.

“If the Obama administration were serious about protecting the public on public health, they would immediately move to clamp down on the way e cigarettes are being advertised and apply the same rules that apply to cigarette advertising,” Glantz says.

Those rules include bans on sports sponsorships, cartoon characters, flavors and TV advertising.

Blu eCigs use a cartoon character named Mr. Cool on its website and YouTube. (Sound familiar? Some have noticed similarities between the ways the e cigarette industry has marketed its product and how traditional tobacco companies have. Here, a House committee compares the two.)

Blu maker Lorillard has not responded to NPR’s requests for comment. Blu’s website asks if you are 18 to enter, and ads say “not for minors.”

Willmore says nonetheless, they re glamorize smoking and threaten to reverse decades of progress in preventing kids from getting hooked.

“Kids may view them as something they can use that’s not going to harm their health without realizing that they contain very addictive nicotine,” Willmore says. “For kids, these products could serve as a gateway to nicotine addiction and even to regular cigarette smoking.”